1000+ Chemical Engineering Thermodynamics MCQ for SSC Stenographer [Solved]

1. Sound waves propagation in air exemplifies an __________ process.
A. Adiabatic
B. Isothermal
C. Isometric
D. None of these
Answer : A

2. Entropy is a/an
A. State function
B. Macroscopic property
C. Extensive property
D. None of these
Answer : D

3. Lenz's law results from the law of conservation of
A. Mass
B. Momentum
C. Energy
D. None of these
Answer : C

4. For the gaseous phase chemical reaction, C₂H₄(g) + H₂O(g) ? C₂H₅OH(g), the equilibrium conversion does not depend on the
A. Steam to ethylene ratio
B. Temperature
C. Pressure
D. None of these
Answer : D

5. The value of gas constant 'R' is
A. 1.987 cal/gm mole °K
B. 1.987 BTU/lb. mole °R
C. Both (A) and (B)
D. Neither (A) nor (B)
Answer : C

6. In a homogeneous solution, the fugacity of a component depends upon the
A. Pressure
B. Composition
C. Temperature
D. All (A), (B) and (C)
Answer : D

7. Dry ice is
A. Moisture free ice
B. Solid helium
C. Solid carbon dioxide
D. None of these
Answer : C

8. For a real gas, the chemical potential is given by
A. RT d ln P
B. RT d ln f
C. R d ln f
D. None of these
Answer : B

9. The change in __________ is equal to the reversible work for compression in steady state flow process under isothermal condition.
A. Internal energy
B. Enthalpy
C. Gibbs free energy
D. Helmholtz free energy
Answer : C

10. For a constant volume process
A. dE = C_pdT
B. dE = C_vdT
C. dQ = dE + pdV
D. dW = pdV
Answer : B

11. A gas can be liquefied by pressure alone only, when its temperature is __________ its critical temperature.
A. Less than
B. More than
C. Equal to or higher than
D. Less than or equal to
Answer : D

12. A domestic refrigerator has a/an __________ cooled condenser.
A. Water
B. Air
C. Evaporative
D. Gas
Answer : B

13. Joule-Thomson Co-efficient at any point on the inversion curve is
A. ?
B. +ve
C. 0
D. -ve
Answer : C

14. After throttling, gas temperature
A. Decreases
B. Increases
C. Remain same
D. May increase or decrease; depends on the nature of the gas
Answer : A

15. Generation of heat by friction is an example of a/an __________ change.
A. Isothermal
B. Irreversible
C. Adiabatic
D. Reversible
Answer : B

16. What is the value of Joule-Thomson co-efficient for an ideal gas?
A. +ve
B. -ve
C. 0
D. ?
Answer : C

17. The equation, (d log_e PA/d log_e xA) = (d log_e PA/d log_e xB) applicable to a binary solution of components. A and B in equilibrium with their vapors at constant temperature and pressure is called the __________ equation.
A. Van Laar
B. Margules
C. Gibbs-Duhem
D. Gibbs-Duhem-Margules
Answer : D

18. Gibbs free energy of a pure fluid approaches __________ as the pressure tends to zero at constant temperature.
A. Infinity
B. Minus infinity
C. Zero
D. None of these
Answer : B

19. Number of phases in a colloidal system is:
A. 1
B. 2
C. 3
D. 4
Answer : B

20. A system is said to be at equilibrium, if the entropy of the system has reached __________ value.
A. Minimum
B. Zero
C. Maximum
D. None of these
Answer : C

21. Efficiency of a heat engine working on Carnot cycle between two temperature levels depends upon the
A. Two temperatures only
B. Pressure of working fluid
C. Mass of the working fluid
D. Mass and pressure both of the working fluid
Answer : A

22. Pick out the wrong statement.
A. The chemical potential of a pure substance depends upon the temperature and pressure
B. The chemical potential of a component in a system is directly proportional to the escaping tendency of that component
C. The chemical potential of ith species (?_i) in an ideal gas mixture approaches zero as the pressure or mole fraction (x_i) tends to be zero at constant temperature
D. The chemical potential of species 'i' in the mixture (?_i) is mathematically represented as,?_i = ?(nG)/?ni]_T,P,nj where, n, n_i and n_j respectively denote the total number of moles, moles of i^th species and all mole numbers except ith species. 'G' is Gibbs molar free energy
Answer : C

23. An ideal liquid refrigerant should
A. Not have a sub-atmospheric vapour pressure at the temperature in the refrigerator coils
B. Not have unduly high vapour pressure at the condenser temperature
C. Both (A) and (B)
D. Have low specific heat
Answer : C

24. Gibbs-Helmholtz equation is
A. ?F = ?H + T [?(?F)/?T]P
B. ?F = ?H - T?T
C. d(E - TS) T, V < 0
D. dP/dT = ?H_vap/T.?V_vap
Answer : A

25. The entropy change in a reversible isothermal process, when an ideal gas expands to four times its initial volume is
A. R log_e 4
B. R log₁₀ 4
C. C_v log₁₀ 4
D. C_v log_e 4
Answer : A

26. For an ideal gas, the activity co-efficient is
A. Directly proportional to pressure
B. Inversely proportional to pressure
C. Unity at all pressures
D. None of these
Answer : C

27. Mollier chart is a __________ plot.
A. Pressure vs. enthalpy
B. Pressure vs. volume
C. Enthalpy vs. entropy
D. Temperature vs. entropy
Answer : C

28. Rotary lime kiln is an example of a/an __________ system.
A. Closed
B. Open
C. Isolated
D. Non-thermodynamic
Answer : B

29. Trouton's ratio of __________ liquids is calculated using Kistyakowsky equation.
A. Polar
B. Non-polar
C. Both (A) & (B)
D. Neither (A) nor (B)
Answer : B

30. The chemical potential of any constituent of an ideal solution depends on the __________ of the solution.
A. Temperature
B. Pressure
C. Composition
D. All (A), (B) and (C)
Answer : D

31. The extensive properties are
A. Volume, mass and number of moles
B. Free energy, entropy and enthalpy
C. Both (A) and (B)
D. None of these
Answer : C

32. For the reversible exothermic reaction, N₂ + 3H₂ ? 2NH₃, increase of pressure would
A. Shift the equilibrium towards right
B. Give higher yield of NH₃
C. Both (B) and (C)
D. Neither (A) nor (B)
Answer : C

33. Which of the following equations is used for the prediction of activity co-efficient from experiments?
A. Van Laar equation
B. Margules equation
C. Wilson's equation
D. All (A), (B) and (C)
Answer : D

34. Absolute zero temperature signifies the
A. Minimum temperature attainable
B. Temperature of the heat reservoir to which a Carnot engine rejects all the heat that is taken in
C. Temperature of the heat reservoir to which a Carnot engine rejects no heat
D. None of these
Answer : C

35. Pick out the wrong statement.
A. Cp of monatomic gases such as metallic vapor is about 5 kcal/kg.atom
B. The heat capacity of solid inorganic substance is exactly equal to the heat capacity of the substance in the molten state
C. There is an increase in entropy, when a spontaneous change occurs in an isolated system
D. At absolute zero temperature, the heat capacity for many pure crystalline substances is zero
Answer : B

36. For an ideal liquid solution, which of the following is unity?
A. Activity
B. Fugacity
C. Activity co-efficient
D. Fugacity co-efficient
Answer : C

37. The efficiency of a Carnot heat engine operating between absolute temperatures T₁ and T₂ (when, T₁ > T₂) is given by (T₁ - T₂)/T1. The co-efficient of performance (C.O.P.) of a Carnot heat pump operating between T₁ and T₂ is given by
A. T₁/(T₁-T₂)
B. T₂/(T₁-T₂)
C. T₁/T₂
D. T₂/R₁
Answer : A

38. On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will
A. Increase
B. Decrease
C. Remain same
D. Increase in summer and will decrease in winter
Answer : A

39. Critical temperature is defined as the temperature above which a gas will
A. Not liquify (barring exceptions)
B. Immediately liquify
C. Never liquify however high the pressure may be
D. None of these
Answer : C

40. In any spontaneous process, the __________ free energy decreases.
A. Helmholtz
B. Gibbs
C. Both a & b
D. Neither 'a' nor 'b'
Answer : C

41. All gases above its inversion temperature, in a throttling process will show
A. A heating effect
B. No change in temperature
C. A cooling effect
D. Either (A) or (C)
Answer : A

42. Fundamental principle of refrigeration is based on the __________ law of thermodynamics.
A. Zeroth
B. First
C. Second
D. Third
Answer : C